Conveyer system for drum-type photoprinter



AprillZ, 1949. P. B. STREICH 2,467,241

CONVEYER SYSTEM FOR DRUM TYPE PHOTOPRINTER Original Filed Feb. 20, 1945 INVENTOR. R404 5 STPf/Cf/ A T TOA /VZVS Patented Apr. 12, 1949 CONVEYER SYSTEM FOR DRUM-TYPE PHOTOPRINTER Paul B. Streich, Maywood, Ill., assignor to Charles Brunmg Company, Inc., Chicago, 111., a corporation of New York Original application February 20, 1945, Serial No. 578,840. Divided and this application June 21, 1946, Serial No. 678,513

1 Claim. 1

This invention relates to improvements in printing machines for sensitized material, and more particularly, to printing means of the general type in which sensitized material such as paper, is fed around a revolving light-transmitting or transparent cylinder containing lighting or illuminating means adapted for printing purposes, the tracings or the like of which prints are to be made, being fed between the sensitized material and the cylinder.

This application is a division of application Serial No. 578,840, filed February 20, 1945, now Patent 2,431,520.

As is described in said application, it has been diflicult to remove tracings and the like from the sensitized paper or material in machines of this type and to provide uniform cooling of the lighttransmitting or transparent cylinders therein.

An important object of this invention is to utilize the cooling means described in this and the aforementioned copending application for the separation of tracings from the xposed printing paper or other material.

Another object of the present invention is to provide apparatus of the character specified in which a partial vacuum maintained in the casing is utilized to separate tracings and the like from the sensitized paper.

A further object is to provide apparatus of the general type referred to in which exhaust means for the casing draws air from the outside through duct means to the interior of the revolving cylinder at an intermediate'part, draws the heated air from both ends of the cylinder into the casing, and draws air into the casing and over the cylinder to cool the cylinder, the bands and the upper part of the casing and to separate the tracings from the exposed paper or the like.

Another object is to provide apparatus of the general type referred to in which the partial vacuum maintained in the casing is utilized to maintain the tracings and the printing paper or other material in juxtaposition on the bands after the operator has placed them thereon and prior to their passage around the transparent cylinder.

Other objects, features, and advantages will appear upon consideration of the following detailed description and of the drawings, in which:

Figure 1 is a view in transverse vertical section of printing apparatus embodying one feature of the invention; and

Figure 2 is a section taken along the line 2-2 of Figure 1.

Referring to the drawings, the printer comprises apparatus within a casing 10, having a 2 bottom I I, a front wall l2, a rear wall 13, a right side Wall 14, a left side wall l5 and a top l6. Mounted transversely of the casing l0, and in the upper part thereof, is a rotatable light-transmitting cylinder ll of heat resisting material such as Pyrex. A suitable lamp l8, such as a mercury vapor lamp, is mounted coaxially of said cylinder H, the cylinder receiving tracings I9 and sensitized paper 20 on the outer surface thereof. The cylinder I1 is suitably mounted for rotation about its axis, as for example, by being suspended by a series of endless bands 23 which also serve to hold the tracings l9 and the sensitized paper against the rotating cylinder ll. Instead of a series of endless bands, as above described, it is contemplated that a perforated band would be used.

Said bands 23 pass upwardly and rearwardly over a 101124 to a roll 25 adjacent to the front of cylinder ll, thus providing a traveling platform to receive the tracings and paper from a feed board 25. From the roll 25 the sensitized paper and the tracings are fed around the cylin-- der between the same and bands 23 until they pass over the top of the cylinder H where the bands leave the cylinder and run forwardly and substantially horizontally to the bottom of a roll 21, upwardly at its front and rearwardly to a roll 28 at the rear part of the casing. At the rear of roll 28, the bands pass downwardly to a roll 29, forwardly from the bottom of the roll to the bottom of the roll 39, and from th same upwardly to roll 24.

The heat generated by lamp I8, unless dissipated, would injure the sensitized paper and otherwise impair the printing operation. In accordance with this invention, the lamp and cylinder [1 are cooled by providing an exhaust outlet 3| in the back or rear wall I3, preferably in the lower part of the casing, and an exhaust fan 32 to force air outwardly through said outlet, thereby drawing in cool air through openings provided in the casing.

According to the present invention, substantially uniform cooling of the cylinder [1 may be obtained, and this cooling is effected by means of air flow induced by said fan 32. To this end, the cylinder ends are spaced inwardly from the side walls It and 15 to permit the fiow of air around such ends of the cylinder H, as indicated by the arrows in Figure 2. Beyond said cylinder ends are provided openings 33 and 34 covered by caps 35 and 35. Extending through the cylinder H and through suitable close-fitting openings in the caps 35 and 36, is a duct 31 which is open at both ends to receive the outside air.

The duct 31 is of substantial cross-section and preferably is shaped in such a manner that the side adjacent the cylinder I! is cylindrical, preferably having a curvature about the axis of the cylinder l1. It will be observed that the duct 31 serves as a light shield to prevent light from reaching the portion of the cylinder I] where the tracing and print are not in contact. The narrow face of the duct facing rearwardly with reference to the rotation of the cylinder is provided with a series of air passages 38 from which the air passes in a clockwise direction around the interior of the cylinder and due to the drawing out of the air through the ends of the cylinder by means of the fan 32, the air passes in helical currents, as indicated by the arrows in Figure 2, to the ends of the cylinder where it passes between said ends and the sides of the casing into the main part of the casing, the flow into the main casing being influenced by the chambers within the caps '35 and 36. Air is also drawn into the casing above the feed board 26, as indicated by the corresponding arrows on Figure 1, thus producing a cooling effect at the interior of the casing.

According to another feature of the invention, outside air is drawn into the casing above the cylinder I! through an opening 2| in the front of the casing, as indicated by the corresponding arrows on Figure 1, and at this point, the vacuum chamber is utilized to separate the tracings from the sensitized paper, thus eliminating the need for a special device to effect such separation. To

this end, there is provided a receiving tray .39 extending across the front of the casing and connected to the side walls thereof. Said tray 39 includes a curved bottom 40 and a substantially horizontal portion over the bands between the rolls 24 and 25. A stripping edge 22 is formed on the tray 39 either to engage the cylinder H yieldingly, or to be spaced slightly away therefrom.

Each tracing l9 with the sensitized paper heneath it is fed from the feed board 26 over a horizontal stretch of bands 23 to the cylinder I! and retained in juxtaposition on said bands until the tracing comes into contact with cylinder I! by means of the suction maintained within the casing 10 by exhaust fan 32 as reflected in the flow of air into said casing between feed board 26 and cylinder ll. Each tracing, with the sensitized paper thereunder, is then carried around the cylinder 11 to the top thereof. There-the sensitized paper is held against the lower sides of the bands 23 by the partial vacuum in the casing and fed forwardly beneath the bands. Inasmuch as the partial vacuum in the casing does not attract the tracing due to the fact that the sensitized paper is essentially nonporous, the tracings are separated by gravity and air agitation and fall into tray 39. After the exposed paper reaches roll 27, the bands continue in their movement and pass around the roll 2! from below, and then rearwardly as hereinbefore described, the guide fingers M assisting the printing paper around roll 42 en its way to a developer unit above said casing It should be understood that various changes may be made, and that various features may be used without others, without departing from the true scope and spirit of the invention.

Iclaim:

In a machine of the character described, the combination with a light-transmitting cylinder, illuminating means in said cylinder and band means for feeding sensitized sheet material and tracings to the cylinder and maintaining the same in contact with the cylinder during the printing operation, means to support the band means to move from a feeding point toward the cylinder and to hold the bands against the cylinder over a portion of its periphery, a casing'enclosing such cylinder and band means, means for maintaining a partial vacuum in the casing, and an opening in the casing about the portion of the bands moving from the feed point to the cylinder, said opening forming an air inlet over which the sheet material and tracings pass as they are carried toward said cylinder by the band means whereby cooling air is drawn through said air inlet into the casing through said band means to hold the sensitized material and tracing against said band means.

PAUL B. STREICH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,515,614 Pinder Nov. 18, 1924 1,701,317 Stokes Feb. 5, 1929 1,724,077 Fleischer Aug. 13, 1929 1,980,188 Cullen et al. Nov. 13, 1934 2,311,849 MacDonald Feb. 23, 1943 

